An INR of 1.8-2.4 was associated with the lowest incidence rate of major bleeding or thromboembolic events (≤4 events per 100 patient-years) in Chinese patients receiving warfarin.
Cohort (n=491)
No
Does a lower achieved INR range of 1.8-2.4 reduce the incidence of major bleeding and thromboembolic events compared to standard INR ranges in Chinese patients receiving warfarin?
In Chinese patients receiving warfarin, an achieved INR of 1.8-2.4 was associated with the lowest combined risk of major bleeding and thromboembolism, suggesting a lower optimal target than the standard 2.0-3.0.
AIM: To examine the optimal range of International Normalized Ratio (INR) for Chinese patients receiving warfarin for moderate-intensity anticoagulation. METHODS: This was a retrospective cohort study conducted at the ambulatory setting of a 1400-bed public teaching hospital in Hong Kong. The INR measurements and occurrence of serious or life-threatening haemorrhagic and thromboembolic events among patients newly started on warfarin from 1 January 1999 to 30 June 2001 for indications with target INR 2-3 were analysed. The INR-specific incidence of bleeding and thromboembolism were calculated. RESULTS: A total of 491 patients were included, contributing to 453 patient-years of observation period. Forty-seven of the 491 patients experienced 25 haemorrhagic events (5.5 per 100 patient-years) and 27 thromboembolic events (6.0 per 100 patient-years). The percentage of patient-time spent within therapeutic INR range (2-3), INR 3 were 50, 44 and 6%, respectively. The incidence of either haemorrhagic or thromboembolic events was lowest (< or =4 events per 100 patient-years) at INR values between 1.8 and 2.4. CONCLUSIONS: An INR of 1.8-2.4 appeared to be associated with the lowest incidence rate of major bleeding or thromboembolic events in a cohort of Hong Kong Chinese patients receiving warfarin therapy for moderate-intensity anticoagulation.
You et al. (Wed,) conducted a cohort in moderate-intensity anticoagulation (n=491). Warfarin was evaluated on Serious or life-threatening haemorrhagic and thromboembolic events. An INR of 1.8-2.4 was associated with the lowest incidence rate of major bleeding or thromboembolic events (≤4 events per 100 patient-years) in Chinese patients receiving warfarin.